Mixing microphones for wireless headsets

ABSTRACT

An audio playback system may be adaptable to various situations for improved user experience and audio playback quality. For example, earbuds may be both worn by a same user, worn by two different users within audio range of one another, worn by two different users outside of audio range of one another, etc. A second earbud with a secondary microphone operates in a second mode in which it captures audio and encodes it for transmission to the first earbud having a primary microphone. The first earbud with the primary microphone operates in a first mode in which it mixes the audio received from the second earbud with audio received through its own microphone for playback. The first earbud in the first mode may also delay its own microphone stream to compensate for wireless transmission delay and correlate the two audio streams to improve audio quality in case there are sounds that can be picked up by both microphones.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of the filing date of U.S.Provisional Patent Application No. 62/779,192 filed Dec. 13, 2018, thedisclosure of which is hereby incorporated herein by reference.

BACKGROUND

Due to limitations in the short range wireless communication standards,wireless earbuds only support one of the buds serving as the “active”microphone which captures audio and transmits it to a host device duringa phone call, whereas the other earbud has the “inactive” microphone.This presents a user experience problem for users as they are unable toeasily share their bud with a friend while on a phone call even thoughthere is a reasonable expectation that the “3-way” call would workseamlessly.

BRIEF SUMMARY

The present disclosure provides an audio playback system adaptable tovarious situations for improved user experience and audio playbackquality. According to one example, the audio playback system includestwo earbuds, and the various situations to which the earbuds adaptinclude differences in how the earbuds are worn. For example, theearbuds may be both worn by a same user, worn by two different userswithin audio range of one another, worn by two different users outsideof audio range of one another, etc. A second earbud with a secondarymicrophone, which conventionally served as the “inactive” microphone instandards, operates in a second mode in which it captures audio andencodes it for transmission to the first earbud having a primarymicrophone, which conventionally served as the “active” microphone instandards. The first earbud with the primary microphone operates in afirst mode in which it mixes the audio received from the second earbudwith audio received through its own microphone for playback. The firstearbud in the first mode may also delay its own microphone stream tocompensate for wireless transmission delay and correlate the two audiostreams to improve audio quality in case there are sounds that can bepicked up by both microphones. In the situation where two remote usersare wearing the earbuds, audio data captured by the first earbud may betransmitted over a sideband channel to the second earbud for mixing andplayback as a local sidetone.

One aspect of the disclosure provides a system for playing back audio,the system including a first device. The first device includes amicrophone configured to capture first audio information fortransmission to a host computing device, and one or more firstprocessors configured to receive second audio information from a seconddevice over a sideband channel between the first device and the seconddevice, and mix the second audio information from the second device withthe first audio information from the first device. The system mayfurther include the second device wirelessly coupled with the firstdevice, wherein the second device includes a second microphoneconfigured to operate in a secondary role wherein it captures the secondaudio information for transmission to the first device over the sidebandchannel.

According to some examples, the one or more first processors of thefirst device may be configured to determine whether the first device andthe second device are worn by the same person, and perform echocancellation when the first device and the second device are worn by thesame person. The first device may further include a first speaker,wherein the one or more first processors of the first device are furtherconfigured to determine whether the first device is within audio rangeof the second device. In response to determining that the first deviceis not within audio range of the second device, in some examples, thefirst device plays the mixed microphone data as a sidetone through thefirst speaker. In response to determining that the first device is notwithin audio range of the second device, in other examples, the firstdevice transmits the audio information captured by the first microphoneto the second device over the sideband channel. The second device mixesthe received first audio information from the first device with thesecond audio information captured by the second microphone and plays,through the second speaker, the mixed audio information as a sidetone.

The second device may further include one or more second processorsconfigured to determine whether the first device is within audio rangeof the second device. The second device may be further configured tolisten to audio transmitted over a wireless connection between the firstdevice and the computing device when the first device is not withinaudio range of the second device, and play the audio data received bythe listening as a local sidetone.

Another aspect of the disclosure provides a method for playing backaudio. The method includes operating, by a first microphone of a firstdevice, in primary role wherein the first microphone captures audioinformation for transmission from the first device to a host computingdevice, operating, by a second microphone of a second device, in asecondary role wherein the second microphone captures audio informationfor transmission from the second device to the first device over asideband channel, and mixing, by one or more first processors of thefirst device, the audio information from the second device with theaudio information from the first device.

Yet another aspect provides a method, including capturing, by a firstmicrophone of a first device, first audio information for transmissionfrom the first device to a host computing device, receiving, by thefirst device, second audio information from a second device over asideband channel, and mixing, by one or more first processors of thefirst device, the audio information from the second device with theaudio information from the first device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pictorial diagram illustrating an example use of anauxiliary device according to aspects of the disclosure.

FIG. 2 is a pictorial diagram illustrating another example use of anauxiliary device according to aspects of the disclosure.

FIG. 3 is a pictorial diagram illustrating another example use of anauxiliary device according to aspects of the disclosure.

FIG. 4 is a functional block diagram illustrating an example systemaccording to aspects of the disclosure.

FIG. 5 is a flow diagram illustrating an example method executed by anaudio device with a primary microphone according to aspects of thedisclosure.

FIG. 6 is a flow diagram illustrating an example method executed by anaudio device with a secondary microphone according to aspects of thedisclosure.

FIG. 7 is a flow diagram illustrating a first example method executed bya system according to aspects of the disclosure.

FIG. 8 is a flow diagram illustrating a second example method executedby a system according to aspects of the disclosure.

FIG. 9 is a flow diagram illustrating a third example method executed bya system according to aspects of the disclosure.

DETAILED DESCRIPTION Overview

A sideband channel between two audio playback devices, such as twoearbuds, may be used to transmit microphone data from a second devicewith an “inactive” microphone to a first device with an “active”microphone. As used in this disclosure, “active” and “inactive” do notnecessarily refer to whether the microphones capture audio, but ratherrefer to whether the microphones are in a primary device directlyconnected to a host or a secondary device. The first device mixes themicrophone data as it comes in. This solution is seamless, in that theuser's voice is captured regardless of whether the first device havingthe primary microphone is worn by the user, by another user, or not wornat all.

To minimize delay resulting from the second device encoding andtransmitting data, the data may in some examples by encoded as L2CAP andmixed in on the first device as it is received. This should alleviatebandwidth and performance concerns of trying to maintain two activeisochronous audio connections. Reducing the delay should also reduceecho in the first device. Echo may be further reduced by, for example,using echo cancellation to omit the secondary microphone data from thesecond device altogether if the system detects that the same user iswearing both the first and second devices. As another example, the echocancellation may be used in combination with a determination of whetherthe user wearing both devices is speaking.

Determining whether one person is wearing both devices may be performedby, for example, comparing a power and signal of each device. Forexample, if the same user is wearing both devices, such as two earbuds,power and signal may be roughly the same with a temporal shift. Incontrast, if a different user is wearing each of the two devices, adifferent power and signal as well as the temporal shift may be evident.In other examples, external signals, such as detection of whether theuser is speaking, identification of voice parameters received in eachmicrophone, etc., may be used to distinguish one wearer vs multiplewearers.

When two separate users are wearing the devices, and are separated fromeach other over a distance such that they are not within earshot of oneanother, the user wearing the second device with the inactive microphonewould typically not hear what the other user is saying. To resolve this,in one example, the second device having the secondary microphone mayspy on an audio connection between the first device and a wirelesslycoupled computing device. For example, where the first device is awireless earbud coupled to a mobile phone through a Bluetoothconnection, the second device may listen in on audio transmitted fromthe first device to the phone over that connection. The second devicemay play the audio received from such spying as a local sidetone. Thefirst device may play the mixed microphone data as a sidetone. Inanother example, the first device may send its microphone data to thesecond device for mixing and playback as a local sidetone. In yetanother example, only the first device plays the mixed sidetone,potentially using on-head detect (OHD) transitions to determine whetherthe devices are being worn (e.g., on head or not), and to determinewhich device has the active microphone based on whether it is beingworn.

Example Systems

FIG. 1 illustrates an example of a user 101 wearing a first audioplayback device 190 and a second audio playback device 180. In thisexample, the first and second devices 180, 190 are earbuds. In otherexamples, however, the first and second device may be other types ofdevices, of the same type or different types. For example, the firstdevice may be an in-ear speaker/microphone while the second device is asmartwatch or a head-mounted display apparatus.

As shown in FIG. 1, the second device 180 is coupled to the first device190 via a connection 185. The connection 185 may include a standardshort-range wireless coupling, such as a Bluetooth connection. Theconnection 185 may further include a primary isochronous audio channel,such as for standard Bluetooth transmission, as well as a sidebandchannel, such as a separate isochronous audio channel.

Each of the second device 180 and the first device 190 have amicrophone, with only one of the microphones operating in a primary modeat a given time. The primary microphone may capture the user's voice andtransmit it to computing device 170, which may be, for example, a mobilephone or other mobile computing device.

The secondary microphone, for example on second device 180, maynevertheless capture the user's voice, and encode it for transmission tothe first device 190 over the sideband channel of connection 185. Eitheror both of the devices 180, 190 may determine that the devices are wornby the same user 101. When the devices are worn by the same user, thefirst device 190, upon receipt of the encoded data from the seconddevice 180, may perform echo cancellation. Such echo cancellation mayinclude omitting the received encoded data, or any of a number of othertechniques.

FIG. 2 illustrates another example where the first user 101 is wearingthe first device 190 and a second user 102 is wearing the second device180. As such, the first device 190 may capture the voice of the firstuser 101 and playback audio for the first user 101, which the seconddevice 180 captures the voice of the second user 102 and plays backaudio for the second user 102. The connection 185 still extends betweenthe first device 190 and the second device 180.

Either or both of the devices 180, 190 may determine if they are withinaudio range of one another. For example, signals passed over theconnection 185 between the devices 180, 190 may be used to determine aphysical distance between the devices. In other examples, second user'svoice may be faintly detected by the first device 190, and the firstuser's voice may similarly be faintly detected by the second device 180.Again in this example, one of the devices, such as the second device180, may have a secondary microphone, while the other device, such asthe first device 190, has a primary microphone. Because the users 101,102 are within close range of one another, the first user 101 should beable to hear the voice of the second user, such as through the earwithout an earbud, and the second user 102 should similarly hear thevoice of the first user 101.

Keeping with the example where the second device 180 has the inactivemicrophone, the second device 180 captures the voice of the second user102, encodes it, and transmits the encoded voice to the first device 190over the sideband channel. The first device 190 receives the encodedvoice of the second user 102, and mixes it with the voice of the firstuser captured through the primary microphone. This mixed audio data isthen played back through the first device 190. In some examples, thedevices 180, 190 may determine which user 101, 102 is speaking at agiven time. For example, the devices 180, 190 may cross reference avolume level between their respective microphones. If the sound receivedthrough microphone of the second device 180 is quiet and the soundreceived through the microphone of the first device 190 is loud, then itmay be determined that the user 101 is providing speech input, and viceversa. Determining which user is talking may be useful in a number ofsituations. For example, when mixing audio, volume may be reduced ormuted on a stream for the user that is not actively talking. As anotherexample, determining which use is talking may provide a way for a person(not shown) on the other end of the phone call to see who is talking,such as by seeing an image of the person that is talking on a screen oftheir phone or other device.

FIG. 3 illustrates yet another example, where the second user 102wearing the second device 180 with the secondary microphone is out ofaudio range of the first user 101 wearing the first device 190 with theprimary microphone. In this example, the first and second users 101, 102will not be able to hear each other's voices without the voices beingtransmitted through the microphones of the respective devices 180, 190.

According to a first example, the second device 180 having the secondarymicrophone may spy on audio data transmitted from the first device 190to the mobile device 170 to detect voice input of the first user 101.The second device 180 may play the detected voice input as a sidetone.The first device 190 may play the mixed microphone data, including theencoded voice input from the second device 180 mixed with the voiceinput captured by the first device 190, as a sidetone.

According to a second example, the first device 190 may transmit thecaptured voice of the first user 101 to the second device 180 for mixingby the second device 180. For example, the captured voice of the firstuser 101 may be encoded by the first device 190 and transmitted to thesecond device 180. The second device may mix the received voice of thefirst user 101 with the captured voice of the second user 102, andplayback the mixed audio as a sidetone through the second device 180.

According to yet another example, the first device 190 plays the mixedmicrophone data as a sidetone.

According to an even further example, the first device 190 that iscloser to the mobile device 170 may also transmit the audio stream fromthe mobile device 170 to the second device 180, which can mix the audiostream with audio from the microphone of the first device 190.

FIG. 4 provides an example block diagram of the first auxiliary device190 and the second auxiliary device 180. The auxiliary devices 180, 190can be any of various types of devices, such as earbuds, head-mounteddevice, smartwatches, etc. Each device includes one or more processors391, 381, memory 392, 382, and other components typically present inaudio playback devices and auxiliary devices. While a number ofcomponents are shown, it should be understood that such components aremerely non-limiting examples, and that other components may additionallyor alternatively be included.

The one or more processors 391, 381 may be any conventional processors,such as commercially available microprocessors. Alternatively, the oneor more processors may be a dedicated device such as an applicationspecific integrated circuit (ASIC) or other hardware-based processor.Although FIG. 3 functionally illustrates the processor, memory, andother elements of auxiliary devices 180, 190 as being within the samerespective blocks, it will be understood by those of ordinary skill inthe art that the processor or memory may actually include multipleprocessors or memories that may or may not be stored within the samephysical housing. Similarly, the memory may be a hard drive or otherstorage media located in a housing different from that of the auxiliarydevices 180, 190. Accordingly, references to a processor or computingdevice will be understood to include references to a collection ofprocessors or computing devices or memories that may or may not operatein parallel.

Memory 382 may store information that is accessible by the processors381, including instructions 383 that may be executed by the processors381, and data 384. The memory 382 may be of a type of memory operativeto store information accessible by the processors 381, including anon-transitory computer-readable medium, or other medium that storesdata that may be read with the aid of an electronic device, such as ahard-drive, memory card, read-only memory (“ROM”), random access memory(“RAM”), optical disks, as well as other write-capable and read-onlymemories. The subject matter disclosed herein may include differentcombinations of the foregoing, whereby different portions of theinstructions 383 and data 384 are stored on different types of media.

Data 384 may be retrieved, stored or modified by processors 381 inaccordance with the instructions 383. For instance, although the presentdisclosure is not limited by a particular data structure, the data 384may be stored in computer registers, in a relational database as a tablehaving a plurality of different fields and records, XML documents, orflat files. The data 384 may also be formatted in a computer-readableformat such as, but not limited to, binary values, ASCII or Unicode. Byfurther way of example only, the data 384 may be stored as bitmapscomprised of pixels that are stored in compressed or uncompressed, orvarious image formats (e.g., JPEG), vector-based formats (e.g., SVG) orcomputer instructions for drawing graphics. Moreover, the data 384 maycomprise information sufficient to identify the relevant information,such as numbers, descriptive text, proprietary codes, pointers,references to data stored in other memories (including other networklocations) or information that is used by a function to calculate therelevant data.

The instructions 383 may be executed to improve audio playback and userexperience. For example, the instructions 383 may provide for capturingaudio samples through an secondary microphone, encoding the audiosamples, and transmitting them to the second device 190.

While the first auxiliary device 180 is executing the instructions 383,the second auxiliary device 190 may also be executing instructions 393stored in memory 392 along with data 394. For example, similar to theauxiliary device 180, the auxiliary device 190 may also include memory392 storing data 394 and instructions 393 executable by the one or moreprocessors 391. The memory 392 may be any of a variety of types, and thedata 394 may be any of a variety of formats, similar to the memory 382and data 384 of the auxiliary device 180. While the auxiliary device 180is receiving and encoding speech from the user wearing the auxiliarydevice 180, the second auxiliary device 190 may be listening for andreceiving speech as well through microphone 398. The instructions 393may provide for receiving first microphone data from the microphone 398of the second device, receiving second microphone data from themicrophone 388 of the first device 180, and mixing the first and secondmicrophone data. The mixed microphone data may be used for playbackthrough the second device 190. According to some example, the firstdevice may be configured to mix microphone data as well for playback.Moreover, the first device 180 and second device 190 may be configuredto switch back and forth between roles, such as having a microphone in aprimary role, or having a microphone in a secondary role. Accordingly,while the example of FIG. 4 illustrates a particular set of operationsin each set of instructions, it should be understood that either devicemay be capable of executing either set of instructions, as well asadditional or other instructions. By way of example only, theinstructions 383, 393 may be executed to determine whether the first andsecond devices 180, 190 are worn by the same user, are worn by differentusers within audio range of one another, or worn by different users outof audio range of one another. For example, the devices 180, 190 maydistinguish one wearer from multiple wearers using any of a variety ofvoice recognition techniques, measurement and/or comparison of power,signals, or other information, etc.

The mixed microphone data, or other audio data, may be played throughoutputs 387, 397. The outputs 387, 397 may each include, for example,one or more speakers adapted to provide audible output. In someexamples, the outputs 387, 397 may also include one or more other types,such as displays, tactile feedback, etc.

It should be understood that the auxiliary device 180 and mobile device190 may each include other components which are not shown, such charginginput for the battery, signals processing components, etc. Suchcomponents may also be utilized in execution of the instructions 383,393.

Example Methods

In addition to the operations described above and illustrated in thefigures, various operations will now be described. It should beunderstood that the following operations do not have to be performed inthe precise order described below. Rather, various steps can be handledin a different order or simultaneously, and steps may also be added oromitted.

FIG. 5 is a flow diagram illustrating an example method executed by anaudio device, such as an earbud, having a first microphone operating ina primary role. In block 510, the device captures first audio data, suchas speech input from a user, through the first microphone. In block 520,the device receives secondary microphone data from a second device witha second microphone operating in a secondary mode, for example, over asideband channel.

In block 530, the first device determines whether it is being worn by asame user as the second device. For example, the first device maycompare parameters of the audio data received in blocks 510 and 520,such as decibel, pitch, tone, etc. As another example, the first devicemay make the determination as a function of power, signal strength,distance between the devices, movements of the devices, etc. If thedevices are worn by the same user, the first device performs echocancellation (block 535), for example, by omitting the audio received inblock 520.

If the first device determines that it is being worn by a different userthan the second device, it determines whether the second device iswithin audio range (block 540). For example, it may determine whether itdetects a second voice through its microphone, the second voicecorresponding to the voice data received in block 520. As anotherexample, it may determine based on a computed distance between thedevices.

If the second device is within audio range, the first device mixes thefirst and second audio from blocks 510 and 520, and plays it backthrough a speaker of the first device. If the second device is outsideof audio range, the first device may perform a corrective action. Forexample, the first device may play the mixed microphone data as asidetone (block 550). As another example, the first device may send thefirst microphone data to the second device for mixing and playback as asidetone (block 560).

FIG. 6 is a flow diagram illustrating an example method executed by thesecond device, an audio device with a secondary microphone. In block610, the second device captures audio data, such as a user voice, whichit encodes (block 620) and transmits to the first device having theprimary microphone (block 630). According to some examples, the data maybe encoded as L2CAP to minimize delay.

In block 640, the second device may determine whether it is worn by auser that is remote from a user of the first device. For example, it maybe determined whether the first device is outside of audio range, suchas discussed above in connection with block 540 of FIG. 5. If it is notout of range, it may continue capturing voice in block 610. If it is outof range, however, it may take a corrective action. As one option, thesecond device may spy on voice data transmitted over an audio connectionbetween the first device and a computing device, such as a mobile phone,in block 650. The second device may playback the data is detected byspying as a local sidetone in block 660. As another option, the seconddevice may receive primary microphone data from the first device inblock 655, and in block 665 it may mix the primary microphone datareceived from the first device with the voice data captured in block610. In block 675, it may play the mixed data as a sidetone in thesecond device.

FIG. 7 is a flow diagram illustrating a first example method executed bya system including the first device and the second device. The firstdevice captures the user voice (block 510). The first device furtherreceives secondary microphone data from the second device, determineswhether the first and second devices are worn by the same user andwhether within range, and performs echo cancellation or mixes themicrophone data as described above in connection with FIG. 5. The seconddevice captures, encodes, and transmits secondary microphone data asdescribed above in connection with FIG. 6. It may also determine whetherthe first and second devices are worn by the same person in block 635,and whether the devices are out of range from each other (block 640).While FIG. 7 illustrates both devices as determining whether they areout of range, in some examples the determination may be made by onedevice and communicated to the other.

If the first and second devices are out of range from one another, theymay take a corrective action. In this example, the second device spieson the audio connection between the first device and the computingdevice, and plays back the data as a local sidetone. Meanwhile, thefirst device plays the mixed microphone data as a sidetone.

FIG. 8 is a flow diagram illustrating a second example method executedby the system. Blocks 510-545 and 610-640 may be the same as describedabove in connection with FIGS. 5-7. However, in this example, adifferent corrective action may be taken if the first and second devicesare out of range of one another. In particular, in block 560 the firstdevice may send the primary microphone data captured through the primarymicrophone to the second device. In some examples, the first device mayencode the data prior to sending, such as using L2CAP. The second devicereceives the primary microphone data from the first device (block 655),mixes it with secondary microphone data captured through the microphoneof the second device (block 665), and plays back the mixed microphonedata (block 675).

FIG. 9 is a flow diagram illustrating a third example method executed bythe system. According to this example, when it is determined that thetwo devices are outside of range of each other, the first device havingthe primary microphone plays the mixed microphone data as a sidetone.

Each of the examples above provide for improved audio quality for asingle user, and an improved user experience for multiple users. Forexample, when multiple users are engaged in a phone call through thesame mobile computing device, with each user wearing a separate earbud,the users may nevertheless hear the entire conversation and provideverbal responses without echo or other undesirable audio effects.Because the devices automatically detect whether they are worn by thesame user or by different users, and whether the different users arewithin audio range, the user experience is improved. For example, userswill automatically hear audio and their voice input will be received,regardless of how the devices are worn and without requiring the user tofirst take some action.

Unless otherwise stated, the foregoing alternative examples are notmutually exclusive, but may be implemented in various combinations toachieve unique advantages. As these and other variations andcombinations of the features discussed above can be utilized withoutdeparting from the subject matter defined by the claims, the foregoingdescription of the embodiments should be taken by way of illustrationrather than by way of limitation of the subject matter defined by theclaims. In addition, the provision of the examples described herein, aswell as clauses phrased as “such as,” “including” and the like, shouldnot be interpreted as limiting the subject matter of the claims to thespecific examples; rather, the examples are intended to illustrate onlyone of many possible embodiments. Further, the same reference numbers indifferent drawings can identify the same or similar elements.

The invention claimed is:
 1. A system for playing back audio,comprising: a first device, the first device comprising: a firstmicrophone configured to capture first audio information fortransmission to a host computing device and configured to transmitinformation received from the host computing device to a second deviceover a primary communication channel between the first device and thesecond device; and one or more first processors configured to: receivesecond audio information from the second device over a sideband channelbetween the first device and the second device, the sideband channelbeing separate from the primary communication channel; and mix thesecond audio information from the second device with the first audioinformation from the first device.
 2. The system for playing back audioof claim 1, further comprising: the second device wirelessly coupledwith the first device, the second device comprising: a secondmicrophone, the second microphone configured to operate in a secondaryrole wherein it captures the second audio information for transmissionto the first device over the sideband channel.
 3. The system of claim 1,wherein the one or more first processors of the first device are furtherconfigured to: determine whether the first device and the second deviceare worn by the same person; and perform echo cancellation when thefirst device and the second device are worn by the same person.
 4. Thesystem of claim 1, wherein the first device further comprises a firstspeaker, wherein the one or more first processors of the first deviceare further configured to determine whether the first device is withinaudio range of the second device.
 5. The system of claim 4, wherein inresponse to determining that the first device is not within audio rangeof the second device, the first device plays the mixed first and secondaudio as a sidetone through the first speaker.
 6. The system of claim 4,wherein in response to determining that the first device is not withinaudio range of the second device, the first device transmits the audioinformation captured by the first microphone to the second device overthe sideband channel.
 7. The system of claim 6, wherein the seconddevice mixes the received first audio information from the first devicewith the second audio information.
 8. The system of claim 2, wherein thesecond device further comprises one or more second processors configuredto determine whether the first device is within audio range of thesecond device.
 9. The system of claim 8, wherein the second device isfurther configured to: listen to audio transmitted over a wirelessconnection between the first device and the computing device when thefirst device is not within audio range of the second device; and playthe audio transmitted over the wireless connection between the firstdevice and the computing device as a local sidetone.
 10. A method forplaying back audio, comprising: operating, by a first microphone of afirst device, in primary role wherein the first microphone capturesaudio information for transmission from the first device to a hostcomputing device and transmits information received from the hostcomputing device to a second device over a primary communication channelbetween the first device and the second device; and operating, by asecond microphone of the second device, in a secondary role wherein thesecond microphone captures audio information for transmission from thesecond device to the first device over a sideband channel, the sidebandchannel being separate from the primary communication channel; andmixing, by one or more first processors of the first device, the audioinformation from the second device with the audio information from thefirst device.
 11. The method of claim 10, further comprising:determining, by the one or more first processors, whether the firstdevice and the second device are worn by the same person; and performingecho cancellation when the first device and the second device are wornby the same person.
 12. The method of claim 10, further comprisingdetermining, by the one or more first processors, whether the firstdevice is within audio range of the second device.
 13. The method ofclaim 12, further comprising, in response to determining that the firstdevice is not within audio range of the second device, playing the mixedaudio information as a sidetone through a first speaker of the firstdevice.
 14. The method of claim 12, further comprising, in response todetermining that the first device is not within audio range of thesecond device, transmitting the audio information captured by the firstmicrophone to the second device over a sideband channel.
 15. The methodof claim 14, further comprising mixing, by the second device, the audioinformation from the first device with the audio information captured bythe second microphone.
 16. The method of claim 15, further comprisingplaying, through a second speaker of the second device, the mixed audioinformation as a sidetone.
 17. The method of claim 10, furthercomprising determining, by one or more second processors of the seconddevice, whether the first device is within audio range of the seconddevice.
 18. The method of claim 17, further comprising: listening, bythe second device, to audio transmitted over a wireless connectionbetween the first device and the computing device when the first deviceis not within audio range of the second device; and playing, by thesecond device, the audio transmitted over the wireless connectionbetween the first device and the computing device as a local sidetone.19. A method for playing back audio, comprising: capturing, by a firstmicrophone of a first device, first audio information for transmissionfrom the first device to a host computing device; transmittinginformation received at the first device, from the host computingdevice, to a second device over a primary communication channel betweenthe first device and the second device; receiving, by the first device,second audio information from a second device over a sideband channel,the sideband channel being separate from the primary communicationchannel; and mixing, by one or more first processors of the firstdevice, the audio information from the second device with the audioinformation from the first device.
 20. The system of claim 7, whereinthe second device plays, through the second speaker, the mixed audioinformation as a sidetone.